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Thread: Max-E-Therm 400 service system light on

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    Max-E-Therm 400 service system light on

    I am currently troubleshooting my heater and hit a stuck point. I have a Pentair Max-E-Therm 400 installed approximately April 2012. My pool is an in-ground gunite with attached spa (total approx 30,000 gallons). When I turn on the heater using either the spa or pool selection, the service system light turns on and nothing else happens. I have what I believe to be adequate water flow running through the system. No issues with the pump or filter at this time. Entire plumbing system has been leak checked resulting in no present issues. I have attempted bypassing the pressure switch by bridging the connection wires, but to no avail. The heater still does not fire. I have the spa set to heat to 100 and the pool set to heat to 90. Currently the water temperature is reading at 70. When I set the spa or pool temperature to heat at 70 or below, the service system light turns off. When I unplug either of the two sets of wires on the left side of the housing where the water inlet and output pipes are (I believe they are to a thermal regulator), The service system light turns off and the service heater light came on with an error of E01. Any help on the issue would be appreciated. Any help in regards to the issue at hand will be appreciated. Additionally, there was a point within the last two months where the pool had a severe algae bloom and the chemicals were all out of whack (Hurricane Isaac).

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    Re: Max-E-Therm 400 service system light on

    A "service system" light indicates that the issue is not the heater. If you have a cartridge style filter, remove the cartridge entirely and run the system without it. If you have a DE or sand filter, thoroughly clean them and then try it.

    Do you have automation on your pool? If you do and you have a water temperature sensor installed somewhere inline, it could be bad.
    Paul
    http://www.gastekservices.com A word of caution: When working with gas and electrical you might want to consider a licensed contractor. Consider the value of your life and others around you. If you would like to provide a review of the help I provided, please use the following link to leave a review. gastek - Google Search,

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    Re: Max-E-Therm 400 service system light on

    I have a sand filter system that has been thoroughly backwashed. At this point I am leaning towards more of the issue being one of the heater components.

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    Re: Max-E-Therm 400 service system light on

    Do you have rats/mice in the area? They love to nest in those heaters. Remove the covers(4 X 3/8" screws) and locate the pressure switch.



    Pressure switch is connected to the violet wires in this picture.
    Make sure those two wires have not been chewed, and are still making good contact. This is the switch that(when open) will give you a service system light.

    Note: This picture has not been retouched, pretty incredible huh?
    Factory Warranty Station for:
    Jandy/Zodiac, Pentair, Sta-Rite, Raypak, Polaris,
    and Paramount pool cleaning systems.

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    Re: Max-E-Therm 400 service system light on

    I appreciate the replies so far. There are no mice nests, there were however a few hornet nests within the unit. I have checked all wires and have found no disconnections. I have attempted to troubleshoot the pressure switch to no avail. I connected the wires with the unit on and the service system light remained on. The burner did not kick on.

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    Re: Max-E-Therm 400 service system light on

    Once you get a fault on the heater, you must reset it by disconnecting power. this may not always happen by just turning the pump off you must reset at the breaker to be sure.
    Factory Warranty Station for:
    Jandy/Zodiac, Pentair, Sta-Rite, Raypak, Polaris,
    and Paramount pool cleaning systems.

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    Re: Max-E-Therm 400 service system light on

    Pull the top off and then turn it over and disconnect the board and remove it. You have to disconnect it to look at the bottom side of the board where everything is soldered. Do you see any burned/scorched spots on it? Maybe a small critter got up under the board and cooked a part of the board.
    Paul
    http://www.gastekservices.com A word of caution: When working with gas and electrical you might want to consider a licensed contractor. Consider the value of your life and others around you. If you would like to provide a review of the help I provided, please use the following link to leave a review. gastek - Google Search,

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    Re: Max-E-Therm 400 service system light on

    Will check the board when I get some light out. Thank you.

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    Re: Max-E-Therm 400 service system light on

    I am having the same problem.

    PS LED is lit under the board indicating bad PS but when I jump it the heater still does not work.

    Did you solve your problem?

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    Re: Max-E-Therm 400 service system light on

    This is an old thread but in case someone else with the problem finds it like I did, for me the problem was that I had wired in a new pump and in the process accidentally wired the heater as 110V instead of 240V. So the system came on, but the heater would never fire, it gave me the "service system" light. I connected the second leg of power to give the heater 240V and the error went away.

    The heater can be configured either way so just be ABSOLUTELY SURE that your heater is in fact set up for 240V before you try this (check that the 240V jumper is installed). 110V supplied to a 240V heater setup, no problem, the heater just doesn't work. But apply 240V to a 110V heater setup and you'll instantly fry all the heater's electronic components.

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    Re: Max-E-Therm 400 service system light on

    Thanks for all the folks that contributed to this thread. Momentary panic. Tripped breakers and the heater fired right up.

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